Yahoo rejected Microsoft's $41.6 billion takeover offer as too low on Monday, forcing the software maker either to sweeten the bid or adopt a hostile approach to clinch a deal.

Microsoft responded by calling its offer full and fair, but stopped short of saying it would not raise its offer.

"As we have said previously, Microsoft reserves the right to pursue all necessary steps to ensure that Yahoo's shareholders are provided with the opportunity to realize the value inherent in our proposal," Microsoft said in a statement without specifying what its next course of action would be.

In response to Microsoft's statement, a Yahoo spokesman said it stood by its earlier letter on Monday from the Sunnyvale, California company's board that the Microsoft proposal undervalues Yahoo.

Still, analysts say Microsoft will probably raise its bid, originally valued at $31 a share, to at least $35, but could be persuaded to go as high as $40.